fs/jfs: Inconsistent signed/unsigned types usage in return values

The getblk() returns a value of type grub_int64_t which is assigned to
iagblk and inoblk, both of type grub_uint64_t, in grub_jfs_read_inode()
via grub_jfs_blkno(). This patch fixes the type mismatch in the
functions. Additionally, the getblk() will return 0 instead of -1 on
failure cases. This change is safe because grub_errno is always set in
getblk() to indicate errors and it is later checked in the callers.

Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Alec Brown <alec.r.brown@oracle.com>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Gbp-Pq: Topic cve-2025-jan
Gbp-Pq: Name fs-jfs-Inconsistent-signed-unsigned-types-usage-in-return.patch

diff --git a/grub-core/fs/jfs.c b/grub-core/fs/jfs.c
index 2bde48d45c2d13f5c08ba92bf70326bc9d438542..70a2f494749d7dd9eb81d0d8163dd97c804d8991 100644 (file)
--- a/grub-core/fs/jfs.c
+++ b/grub-core/fs/jfs.c
@@ -279,7 +279,7 @@ get_ext_offset (grub_uint8_t offset1, grub_uint32_t offset2)
   return (((grub_uint64_t) offset1 << 32) | grub_le_to_cpu32 (offset2));
 }
 
-static grub_int64_t
+static grub_uint64_t
 getblk (struct grub_jfs_treehead *treehead,
        struct grub_jfs_tree_extent *extents,
        int max_extents,
@@ -290,6 +290,8 @@ getblk (struct grub_jfs_treehead *treehead,
   int i;
   grub_uint64_t ext_offset, ext_blk;
 
+  grub_errno = GRUB_ERR_NONE;
+
   for (i = 0; i < grub_le_to_cpu16 (treehead->count) - 2 &&
              i < max_extents; i++)
     {
@@ -312,7 +314,7 @@ getblk (struct grub_jfs_treehead *treehead,
 
   if (found != -1)
     {
-      grub_int64_t ret = -1;
+      grub_uint64_t ret = 0;
       struct
       {
        struct grub_jfs_treehead treehead;
@@ -321,7 +323,7 @@ getblk (struct grub_jfs_treehead *treehead,
 
       tree = grub_zalloc (sizeof (*tree));
       if (!tree)
-       return -1;
+       return 0;
 
       if (!grub_disk_read (data->disk,
                           (grub_disk_addr_t) ext_blk
@@ -334,19 +336,20 @@ getblk (struct grub_jfs_treehead *treehead,
          else
            {
              grub_error (GRUB_ERR_BAD_FS, "jfs: infinite recursion detected");
-             ret = -1;
+             ret = 0;
            }
        }
       grub_free (tree);
       return ret;
     }
 
-  return -1;
+  grub_error (GRUB_ERR_READ_ERROR, "jfs: block %" PRIuGRUB_UINT64_T " not found", blk);
+  return 0;
 }
 
 /* Get the block number for the block BLK in the node INODE in the
    mounted filesystem DATA.  */
-static grub_int64_t
+static grub_uint64_t
 grub_jfs_blkno (struct grub_jfs_data *data, struct grub_jfs_inode *inode,
                grub_uint64_t blk)
 {